how low can it go?

Currently using nymgo's sip service. Their rates are incredible! UK mobiles at 2.6c and Swiss mobiles at 9c. My only gripe is they do not support per second billing or sendrpid service (sending the original caller id when forwarding a call).

Can anyone better those rates? or find similar but with the two features mentioned above?

Finally was wondering about the discrepancy in prices, for example voip.ms charges 18c for UK mobiles albeit with a much better feature set, perhaps MartinM would care to comment....

Take a look at Voxbeam, CheapVoipInc and CallWithUs. All allow you to set the outbound caller ID dynamically (though some require it in the From header). The respective owners all participate in this forum.

Voxbeam has one-second billing on most routes and offers a $1 free trial at signup.

Finally was wondering about the discrepancy in prices, for example voip.ms charges 18c for UK mobiles albeit with a much better feature set....

1) Nymgo provides outbound calling only.

Think about that. That's the ultimate cherry-picking.

If EVERY company offered only OUTBOUND calls, how would anybody be able to RECEIVE calls?

2) As you have said, Voip.MS offers far more in terms of features and real North American customer service.

3) AFAIK, Nymgo does not let you specify an outbound Caller ID number. When I tried it a couple of years ago, the outbound caller ID showed up as some 4-digit code, as I recall.

4) Nymgo is not so much a company as a social experiment.

They have two big sugar daddies:

a) Intel Capital (yes, THAT Intel) who has a vested interest in promoting all types of IP usage.

b) Abraaj Capital, a very well-funded worldwide investment group based in Dubai, UAE. They have the deep pockets to be able to subsidize companies in the short term so as to have those companies dominate in the long term. Abraaj is the parent of Riyada Enterprise Development (RED) which is the specific entity that invested in Nymgo. Riyada invests in companies in Lebanon, and Lebanon is where Nymgo got started though they now also have UK and Luxembourg offices.